How To Insulate Windows: 8 Methods for Year-Round Comfort

You’ve probably made a habit of cranking the heat or AC whenever the season changes. If you’re looking for more sustainable ways to help keep your home comfortable all year long, we have eight different methods for you to improve your window insulation. Lower your energy bills with window insulation tips that work best for you.

1. Use Window Insulation Film

Window insulation film is a plastic shrink film applied to the indoor window frame with double-stick tape. This film reflects hot UV rays during the summer and reduces indoor heat loss during the winter. You can find window insulation kits at your local hardware store or online. They typically cost between $10 and $15.

Applying insulation film to your windows takes 5 easy steps:

• Step 1: Clean the window to remove dirt and ensure a lint-free surface before application.
• Step 2: Apply adhesive tape around the entire window frame as a base for the film.
• Step 3: Slowly peel the film from its sheet and firmly press it onto the adhesive-taped frame. Work your way from one corner to the other, smoothing out any air bubbles and wrinkles as you go.
• Step 4: Carefully trim off excess film edges.
• Step 5: Following the manufacturer instructions, use a hair dryer on the high setting to quickly run heat over the surface. This will shrink the film and help remove any remaining wrinkles.

2. Install Draft Snakes

A draft snake or draft stopper is a long fabric tube stuffed with insulating materials you can place in front of window sills or the base of the door to block drafts. Various door snake styles and shapes are available, including online, making it easy to find one that fits your door width and style. Door snakes typically cost between $15 and $30.

To insulate your windows with draft snakes, simply place a draft snake along the window sill or door. Use additional draft snakes to do the same on other windows and doors throughout the house.

3. Caulk the windows

Using caulk is probably the most common form of winter window insulation. It’s low-cost and relatively easy to do. You can find caulk at any hardware store. For best results, consider using weatherstripping with caulking. For both of these items combined, you can expect to pay between $15 and $30.

Effectively insulate your windows with caulk in four steps:

• Step 1: Clean off any dirt and debris from the window frame and edges.
• Step 2: Use a caulking gun to apply a continuous strand of caulk along the window casing. Fill any cracks and gaps as you go. Be sure not to caulk weep holes.
• Step 3: Let the caulk completely dry (possibly overnight).
• Step 4: Repeat this process on other windows as needed.

4. Use Rubber Weather Sealing

Rubber weather sealing are rubber strips designed to cover any gaps or cracks in your window frame. You can purchase them at any hardware store or online for around $10 to $15. To use rubber weather sealing, simply cut the strips to fit your window dimensions, then peel and stick them to the window frame to help keep out drafts.

5. Hang Heavy Curtains

Thermal or blackout curtains, such as those made of heavy vinyl or linen fabric, are a good way to insulate your windows and decorate the space. They help block out sunlight (and heat) and acts as barrier to drafts. This option, however, can get expensive depending on how many windows you need to cover. The cost of thermal curtains can range anywhere from $100 to $300.

6. Use Cellular Shades

Similar to blackout curtains, cellular shades help block out sunlight and function as window insulation. These types of blinds are designed with unique, honeycomb-shaped air pockets or “cells” that function a layer of insulation.

Keep in mind that cellular shades can be pricey, ranging from $80 to $300 per window.

7. Add Weatherstripping Around Windows

Weatherstripping doors and windows is another easy, low-cost option to seal gaps around windows and doors. You can purchase weatherstripping and caulk together for around $15 to $30.

Apply weatherstripping to windows in four steps:

• Step 1: Measure the length of your window frame and cut the weatherstrip to fit.
• Step 2: Clean the window frame to remove dirt and debris.
• Step 3: Peel the adhesive side of the strip from its covering and apply it firmly to the window frame. Make sure all gaps are completely filled.
• Step 4: Repeat the process on other windows as needed.

8. Add a Secondary Glazing

If it’s within your budget, you can hire a professional to install secondary glazing to your windows. This insulation option is an additional layer of glass or plastic, making your window a double pane once installed. The glaze creates a barrier that not only blocks drafts but also helps with noise reduction.

You can install a third or triple glaze to insulate the window even more. Due to the installation’s complexity, call a professional like Mr. Handyman^® to handle the job.

Prepare Your Home for Winter With Help From Mr. Handyman

If you think your home may require more serious maintenance to improve insulation, Mr. Handyman's service professionals can help. From repairing cracks and gaps to inspecting your HVAC system and current insulation, our team can prepare your home for winter and beyond.

Stay on top of all your household repairs, improvements, and maintenance needs by calling us or requesting service in your area.

This article is intended for general informational purposes only and may not be applicable to every situation. You are responsible for determining the proper course of action for your home and property. Mr. Handyman is not responsible for any damages that occur as a result of this blog content or your actions. For the most accurate guidance, contact your local Mr. Handyman location for a comprehensive, on-site assessment.

Window Insulation FAQs

Mr. Handyman has been helping homeowners repair, maintain, and enhance their spaces for over 25 years! We are the one-stop solution for everything on your to-do list. This includes answering your questions about home repairs, maintenance, and improvements. Here are answers to some of your most frequently asked questions about window insulation.

How do I reduce heat coming through windows?

Window insulation film, which blocks sun rays, is an effective way to reduce heat coming through windows. Window treatments, such as thermal curtains and cellular shades, are also effective.

What is the best insulation around windows?

Window spray foam insulation, such as polyurethane, works best around windows. This insulation foam expands into cracks and gaps in the window frame, creating a tight seal to block drafts.

Is it better to insulate windows from the inside or outside?

While insulation needs vary by home and region, treating your windows from both the inside and outside can be most effective. For example, while caulking and weatherstripping windows outside will seal out drafts and moisture, thermal curtains and insulation film from the inside will block out external heat.